Université Lille Nord de France, USTL, GEPV, CNRS, FRE 3268, F-59650 Villeneuve d'Ascq, France.
Trends Genet. 2011 Nov;27(11):441-5. doi: 10.1016/j.tig.2011.06.005. Epub 2011 Jul 21.
Dominance, its genetic basis and evolution has been at the heart of one of the most intense controversies in the history of genetics. For more than eighty years the existence of dominance modifiers, genetic elements controlling dominance-recessivity interactions, has been suggested as a theoretical possibility, but the modifier elements themselves have remained elusive. A recent study of the self-incompatibility locus in flowering plants provided the first empirical evidence for such genetic elements: small non-coding RNAs that control dominance-recessivity by mediating methylation of the promoter of the recessive allele. Theory has shown that several biological situations are favorable for the evolution of dominance modifiers. We argue that the elucidation of this mechanism of dominance opens up new research avenues that could lead to uncovering dominance modifiers in other genetic systems, such as genes controlling Batesian and Müllerian mimicry or host-parasite interactions, thereby shedding light on the generality of the proposed mechanism.
优势，其遗传基础和进化一直是遗传学史上最激烈争议之一的核心。八十多年来，控制显性-隐性相互作用的遗传调控元件——显性修饰因子的存在一直被认为是一种理论上的可能性，但这些修饰因子本身却难以捉摸。最近对开花植物自交不亲和位点的研究为这些遗传元件提供了第一个经验证据：通过调控隐性等位基因启动子的甲基化来控制显性-隐性相互作用的小非编码 RNA。理论表明，几种生物学情况有利于显性修饰因子的进化。我们认为，对这种显性机制的阐明开辟了新的研究途径，可能会在其他遗传系统中发现显性修饰因子，如控制贝氏拟态和缪勒拟态或宿主-寄生虫相互作用的基因，从而揭示所提出的机制的普遍性。
